/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
/**
 * Copyright (c) 2004-2011 QOS.ch All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining a  copy  of this  software
 *  and  associated  documentation files  (the "Software"), to  deal in  the Software without
 * restriction, including without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to permit persons to whom the
 * Software  is furnished to do so, subject to the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be included in all copies or
 * substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND, EXPRESS OR  IMPLIED,
 * INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF MERCHANTABILITY,    FITNESS    FOR    A
 * PARTICULAR    PURPOSE    AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */
package io.netty.util.internal.logging;

import org.apache.log4j.Level;
import org.apache.log4j.Logger;

/**
 * <a href="http://logging.apache.org/log4j/1.2/index.html">Apache Log4J</a>
 * logger.
 */
class Log4JLogger extends AbstractInternalLogger {

  private static final long serialVersionUID = 2851357342488183058L;

  final transient Logger logger;

  /**
   * Following the pattern discussed in pages 162 through 168 of "The complete
   * log4j manual".
   */
  static final String FQCN = Log4JLogger.class.getName();

  // Does the log4j version in use recognize the TRACE level?
  // The trace level was introduced in log4j 1.2.12.
  final boolean traceCapable;

  Log4JLogger(Logger logger) {
    super(logger.getName());
    this.logger = logger;
    traceCapable = isTraceCapable();
  }

  private boolean isTraceCapable() {
    try {
      logger.isTraceEnabled();
      return true;
    } catch (NoSuchMethodError ignored) {
      return false;
    }
  }

  /**
   * Is this logger instance enabled for the TRACE level?
   *
   * @return True if this Logger is enabled for level TRACE, false otherwise.
   */
  @Override
  public boolean isTraceEnabled() {
    if (traceCapable) {
      return logger.isTraceEnabled();
    } else {
      return logger.isDebugEnabled();
    }
  }

  /**
   * Log a message object at level TRACE.
   *
   * @param msg
   *          - the message object to be logged
   */
  @Override
  public void trace(String msg) {
    logger.log(FQCN, traceCapable ? Level.TRACE : Level.DEBUG, msg, null);
  }

  /**
   * Log a message at level TRACE according to the specified format and
   * argument.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for level TRACE.
   * </p>
   *
   * @param format
   *          the format string
   * @param arg
   *          the argument
   */
  @Override
  public void trace(String format, Object arg) {
    if (isTraceEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, arg);
      logger.log(FQCN, traceCapable ? Level.TRACE : Level.DEBUG, ft
          .getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level TRACE according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the TRACE level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argA
   *          the first argument
   * @param argB
   *          the second argument
   */
  @Override
  public void trace(String format, Object argA, Object argB) {
    if (isTraceEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, argA, argB);
      logger.log(FQCN, traceCapable ? Level.TRACE : Level.DEBUG, ft
          .getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level TRACE according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the TRACE level.
   * </p>
   *
   * @param format
   *          the format string
   * @param arguments
   *          an array of arguments
   */
  @Override
  public void trace(String format, Object... arguments) {
    if (isTraceEnabled()) {
      FormattingTuple ft = MessageFormatter.arrayFormat(format, arguments);
      logger.log(FQCN, traceCapable ? Level.TRACE : Level.DEBUG, ft
          .getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log an exception (throwable) at level TRACE with an accompanying message.
   *
   * @param msg
   *          the message accompanying the exception
   * @param t
   *          the exception (throwable) to log
   */
  @Override
  public void trace(String msg, Throwable t) {
    logger.log(FQCN, traceCapable ? Level.TRACE : Level.DEBUG, msg, t);
  }

  /**
   * Is this logger instance enabled for the DEBUG level?
   *
   * @return True if this Logger is enabled for level DEBUG, false otherwise.
   */
  @Override
  public boolean isDebugEnabled() {
    return logger.isDebugEnabled();
  }

  /**
   * Log a message object at level DEBUG.
   *
   * @param msg
   *          - the message object to be logged
   */
  @Override
  public void debug(String msg) {
    logger.log(FQCN, Level.DEBUG, msg, null);
  }

  /**
   * Log a message at level DEBUG according to the specified format and
   * argument.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for level DEBUG.
   * </p>
   *
   * @param format
   *          the format string
   * @param arg
   *          the argument
   */
  @Override
  public void debug(String format, Object arg) {
    if (logger.isDebugEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, arg);
      logger.log(FQCN, Level.DEBUG, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level DEBUG according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the DEBUG level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argA
   *          the first argument
   * @param argB
   *          the second argument
   */
  @Override
  public void debug(String format, Object argA, Object argB) {
    if (logger.isDebugEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, argA, argB);
      logger.log(FQCN, Level.DEBUG, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level DEBUG according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the DEBUG level.
   * </p>
   *
   * @param format
   *          the format string
   * @param arguments an array of arguments
   */
  @Override
  public void debug(String format, Object... arguments) {
    if (logger.isDebugEnabled()) {
      FormattingTuple ft = MessageFormatter.arrayFormat(format, arguments);
      logger.log(FQCN, Level.DEBUG, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log an exception (throwable) at level DEBUG with an accompanying message.
   *
   * @param msg
   *          the message accompanying the exception
   * @param t
   *          the exception (throwable) to log
   */
  @Override
  public void debug(String msg, Throwable t) {
    logger.log(FQCN, Level.DEBUG, msg, t);
  }

  /**
   * Is this logger instance enabled for the INFO level?
   *
   * @return True if this Logger is enabled for the INFO level, false otherwise.
   */
  @Override
  public boolean isInfoEnabled() {
    return logger.isInfoEnabled();
  }

  /**
   * Log a message object at the INFO level.
   *
   * @param msg
   *          - the message object to be logged
   */
  @Override
  public void info(String msg) {
    logger.log(FQCN, Level.INFO, msg, null);
  }

  /**
   * Log a message at level INFO according to the specified format and argument.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the INFO level.
   * </p>
   *
   * @param format
   *          the format string
   * @param arg
   *          the argument
   */
  @Override
  public void info(String format, Object arg) {
    if (logger.isInfoEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, arg);
      logger.log(FQCN, Level.INFO, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at the INFO level according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the INFO level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argA
   *          the first argument
   * @param argB
   *          the second argument
   */
  @Override
  public void info(String format, Object argA, Object argB) {
    if (logger.isInfoEnabled()) {
      FormattingTuple ft = MessageFormatter.format(format, argA, argB);
      logger.log(FQCN, Level.INFO, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level INFO according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the INFO level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argArray
   *          an array of arguments
   */
  @Override
  public void info(String format, Object... argArray) {
    if (logger.isInfoEnabled()) {
      FormattingTuple ft = MessageFormatter.arrayFormat(format, argArray);
      logger.log(FQCN, Level.INFO, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log an exception (throwable) at the INFO level with an accompanying
   * message.
   *
   * @param msg
   *          the message accompanying the exception
   * @param t
   *          the exception (throwable) to log
   */
  @Override
  public void info(String msg, Throwable t) {
    logger.log(FQCN, Level.INFO, msg, t);
  }

  /**
   * Is this logger instance enabled for the WARN level?
   *
   * @return True if this Logger is enabled for the WARN level, false otherwise.
   */
  @Override
  public boolean isWarnEnabled() {
    return logger.isEnabledFor(Level.WARN);
  }

  /**
   * Log a message object at the WARN level.
   *
   * @param msg
   *          - the message object to be logged
   */
  @Override
  public void warn(String msg) {
    logger.log(FQCN, Level.WARN, msg, null);
  }

  /**
   * Log a message at the WARN level according to the specified format and
   * argument.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the WARN level.
   * </p>
   *
   * @param format
   *          the format string
   * @param arg
   *          the argument
   */
  @Override
  public void warn(String format, Object arg) {
    if (logger.isEnabledFor(Level.WARN)) {
      FormattingTuple ft = MessageFormatter.format(format, arg);
      logger.log(FQCN, Level.WARN, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at the WARN level according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the WARN level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argA
   *          the first argument
   * @param argB
   *          the second argument
   */
  @Override
  public void warn(String format, Object argA, Object argB) {
    if (logger.isEnabledFor(Level.WARN)) {
      FormattingTuple ft = MessageFormatter.format(format, argA, argB);
      logger.log(FQCN, Level.WARN, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level WARN according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the WARN level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argArray
   *          an array of arguments
   */
  @Override
  public void warn(String format, Object... argArray) {
    if (logger.isEnabledFor(Level.WARN)) {
      FormattingTuple ft = MessageFormatter.arrayFormat(format, argArray);
      logger.log(FQCN, Level.WARN, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log an exception (throwable) at the WARN level with an accompanying
   * message.
   *
   * @param msg
   *          the message accompanying the exception
   * @param t
   *          the exception (throwable) to log
   */
  @Override
  public void warn(String msg, Throwable t) {
    logger.log(FQCN, Level.WARN, msg, t);
  }

  /**
   * Is this logger instance enabled for level ERROR?
   *
   * @return True if this Logger is enabled for level ERROR, false otherwise.
   */
  @Override
  public boolean isErrorEnabled() {
    return logger.isEnabledFor(Level.ERROR);
  }

  /**
   * Log a message object at the ERROR level.
   *
   * @param msg
   *          - the message object to be logged
   */
  @Override
  public void error(String msg) {
    logger.log(FQCN, Level.ERROR, msg, null);
  }

  /**
   * Log a message at the ERROR level according to the specified format and
   * argument.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the ERROR level.
   * </p>
   *
   * @param format
   *          the format string
   * @param arg
   *          the argument
   */
  @Override
  public void error(String format, Object arg) {
    if (logger.isEnabledFor(Level.ERROR)) {
      FormattingTuple ft = MessageFormatter.format(format, arg);
      logger.log(FQCN, Level.ERROR, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at the ERROR level according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the ERROR level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argA
   *          the first argument
   * @param argB
   *          the second argument
   */
  @Override
  public void error(String format, Object argA, Object argB) {
    if (logger.isEnabledFor(Level.ERROR)) {
      FormattingTuple ft = MessageFormatter.format(format, argA, argB);
      logger.log(FQCN, Level.ERROR, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log a message at level ERROR according to the specified format and
   * arguments.
   *
   * <p>
   * This form avoids superfluous object creation when the logger is disabled
   * for the ERROR level.
   * </p>
   *
   * @param format
   *          the format string
   * @param argArray
   *          an array of arguments
   */
  @Override
  public void error(String format, Object... argArray) {
    if (logger.isEnabledFor(Level.ERROR)) {
      FormattingTuple ft = MessageFormatter.arrayFormat(format, argArray);
      logger.log(FQCN, Level.ERROR, ft.getMessage(), ft.getThrowable());
    }
  }

  /**
   * Log an exception (throwable) at the ERROR level with an accompanying
   * message.
   *
   * @param msg
   *          the message accompanying the exception
   * @param t
   *          the exception (throwable) to log
   */
  @Override
  public void error(String msg, Throwable t) {
    logger.log(FQCN, Level.ERROR, msg, t);
  }
}
